He had been among the 2,133 runners who took part in the event along Shoebury East Beach, Essex.

David Walpole, a close friend of Mr Palmer's, told the Echo: "He was a great friend and a great father, I have never seen such a committed parent."

Another tribute on the newspaper's website said: "Mate, you were a legend and a pleasure to call a friend for 35 years, some great memories and fantastic laughs over the years...can't put into words how much I'll miss you. R.I.P."

The annual half marathon, which has been held for more than 20 years, is organised by Havens Hospices Group.

A spokesman said: "The male runner collapsed at the finish line and treatment was given immediately by the on-site medic team, then transferred to the medical tent where he was treated by a senior doctor, but he sadly died a short while afterwards. His next of kin have been informed.

"Our thoughts and prayers are with his family and friends at this incredibly sad time."

An Essex Police spokesman said: "Police were called to a medical tent at Ness Road just after midday after a man had collapsed.

"Medical staff tried in vain to revive the man who was aged in his 30s.

"There were no suspicious circumstances and a report will be prepared for the coroner."